USS Sans Souci II (SP-301) was an armed motorboat

Motorboat

A motorboat is a boat which is powered by an engine. Some motorboats are fitted with inboard engines, others have an outboard motor installed on the rear, containing the internal combustion engine, the gearbox and the propeller in one portable unit.An inboard/outboard contains a hybrid of a...

 that served in the United States Navy

United States Navy

The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

 as a patrol vessel from 1917 to 1919.

Sans Souci II was built as a civilian

Civilian

A civilian under international humanitarian law is a person who is not a member of his or her country's armed forces or other militia. Civilians are distinct from combatants. They are afforded a degree of legal protection from the effects of war and military occupation...

 motorboat of the same name in 1907 by the shipyard

Shipyard

Shipyards and dockyards are places which repair and build ships. These can be yachts, military vessels, cruise liners or other cargo or passenger ships. Dockyards are sometimes more associated with maintenance and basing activities than shipyards, which are sometimes associated more with initial...

 of Frank Tregoning at Seattle

Seattle, Washington

Seattle is the county seat of King County, Washington. With 608,660 residents as of the 2010 Census, Seattle is the largest city in the Northwestern United States. The Seattle metropolitan area of about 3.4 million inhabitants is the 15th largest metropolitan area in the country...

, Washington. Following the entry of the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 into World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

, she was enrolled in the Naval Coast Defense Reserve on 15 June 1917. Her owner, D. G. Schmitz of Seattle, delivered her to the U.S. Navy on 9 July 1917 for World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 service as a patrol vessel. She was commissioned

Ship commissioning

Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military...

 as USS Sans Souci II (SP-301) on 1 August 1917 with Chief Boatswain

Boatswain

A boatswain , bo's'n, bos'n, or bosun is an unlicensed member of the deck department of a merchant ship. The boatswain supervises the other unlicensed members of the ship's deck department, and typically is not a watchstander, except on vessels with small crews...

's Mate R. W. Capps, USNRF, in command.

Assigned to local duty within the 13th Naval District, Sans Souci II operated on patrol duty in the Puget Sound

Puget Sound

Puget Sound is a sound in the U.S. state of Washington. It is a complex estuarine system of interconnected marine waterways and basins, with one major and one minor connection to the Strait of Juan de Fuca and the Pacific Ocean — Admiralty Inlet being the major connection and...

 area from Seattle until September 1917. During late 1917, she served briefly as a tender

Ship's tender

A ship's tender, usually referred to as a tender, is a boat, or a larger ship used to service a ship, generally by transporting people and/or supplies to and from shore or another ship...

 to the protected cruiser

Protected cruiser

The protected cruiser is a type of naval cruiser of the late 19th century, so known because its armoured deck offered protection for vital machine spaces from shrapnel caused by exploding shells above...

 USS Philadelphia (Cruiser No. 4)

USS Philadelphia (C-4)

The fourth USS Philadelphia , also known as "Cruiser No. 4", was a cruiser of the United States Navy.She was laid down 22 March 1888 by William Cramp and Sons, Philadelphia, Pennsylvania, launched 7 September 1889, sponsored by Miss Minnie Wanamaker, daughter of merchant and philanthropist John...

, which was the receiving ship at Puget Sound Navy Yard at Bremerton

Bremerton, Washington

Bremerton is a city in Kitsap County, Washington, United States. The population was 38,790 at the 2011 State Estimate, making it the largest city on the Olympic Peninsula. Bremerton is home to Puget Sound Naval Shipyard and the Bremerton Annex of Naval Base Kitsap...

, Washington.

After completing her support duties for Phildaelphia, Sans Souci II resumed patrol duty in Puget Sound, frequently operating with, or alternating with, the submarine chaser

Submarine chaser

A submarine chaser is a small and fast naval vessel specially intended for anti-submarine warfare. Although similar vessels were designed and used by many nations, this designation was most famously used by ships built by the United States of America...

 USS SC-300, until 23 December 1918. She then remained inactive until she was decommissioned

Ship decommissioning

To decommission a ship is to terminate her career in service in the armed forces of her nation. A somber occasion, it has little of the elaborate ceremony of ship commissioning, but carries significant tradition....

 on 7 February 1919 and struck from the Navy List

Navy List

A Navy List or Naval Register is an official list of naval officers, their ranks and seniority, the ships which they command or to which they are appointed, etc., that is published by the government or naval authorities of a country....

 the same day.

Ordered returned to her owner on 26 March 1919, Sans Souci II remained on yacht

Yacht

A yacht is a recreational boat or ship. The term originated from the Dutch Jacht meaning "hunt". It was originally defined as a light fast sailing vessel used by the Dutch navy to pursue pirates and other transgressors around and into the shallow waters of the Low Countries...

registers into the early 1930s, suggesting that she remained in private use until that time.